Advances in technology have enabled the size of personal computers to decrease. As a result, the use of portable computers, such as notebook computers, laptop computers, and notepad computers, is rapidly increasing. The portability of notebook computers and notepad computers enables a user to keep his or her computer readily accessible such that computing resources are effectively always at hand. FIG. 1 illustrates a typical notebook computer with two folding halves, with a display assembly in one half and a base assembly with input devices in the other half. Input devices include, among other things, a keyboard for inputting data and a touchpad for navigating a cursor control. Palm rest areas are areas positioned on the upper surface of the base assembly below the keyboard. They allow a user to rest the base or palm of his or her hands comfortably during typing activity. The vast majority of conventional touchpads that are integrated into portable computers are, in one way or another, isolated from unwanted contact with the user's hands (e.g., during a typing activity). This is usually done by centering the touchpad below the keyboard, and minimizing the size of the touchpad, for example, by not extending the touchpad to the palm rest areas to be formed on either side of the touchpad. The touchpad is also recessed beneath the plane of the palm rest, so that palms, the most common cause of unwanted activation of the touchpad, do not come in contact with the touchpad.
One trend in portable computers has been to make them as desktop computer replacements, which requires them to be larger, while still maintaining their portability features. The display assembly in particular, that includes a display screen, has become larger, to become comparable to the sizes of desktop computer monitors. This has caused the housing of the base assembly to increase proportionally. Large base assembly housings can easily accommodate full-size keyboards, but the size of the touchpads must still be limited because of the high risk of unwanted activation, as discussed above, as well as providing the necessary space for palm rests.
Moreover, in order for larger portable computers to be practical for portability purposes, they must still be relatively thin and light. One conventional method to reduce the overall thickness of portable computers is to mount the touchpad flush with the top surface of the base assembly housing (e.g., the palm rest areas). However, this increases the likelihood of accidental brushing by a user's palms, especially during typing.